Headlight dimmer



June 26, 1923 1.460.309

P. BIERBRAUER ET AL HEADLIGHT DIMMER Filed May 2, 1922 Patented June 2%, 1923.

PAUL BIERBRAUER AND IRVIN DUNCAN PETER-S, OF WAUSAU, WISCONSIN.

HEADLIGHT DIMMER.

Application filed May 2,

T 0 all whom it may concern:

Be it known that we, (1) PAUL BIERBRAUER and (2) IRvIN D. PETERS, citizens of the United States, residing at \Vausau, in the county of Marathon and State of Wisconsin, have invented certain new and useful Improvements in Headlight Dimmers, of which the following'is a specification.

Our invention relates to headlight dimmers and particularly to the type of dimmer which employs a plurality of parallel slats which may be positioned to obstruct certain of the light rays.

Objects of our invention are to improve the construction of dimmers of the type stated and to provide a dimmer including a plurality of parallel slats which normally offer substantially no obstruction to the illuminating power or field of the headlight and which may be readily moved into position to partially or to completely obstruct the passage of light rays to that portion of the field of illumination which lies above the horizontal plane through the headlight. A further object of our invention is to provide a dimmer employing a plurality of metal slat-s and which will be free from noise or chattering when in use on a motor or other vehicle. More specifically an object of our invention is to provide a dimmer in which the parallel slats are mounted in a frame which may be removed as a unit from the dimmer casing.

These and other objects of our invention will be apparent from the accompanying description of one embodiment of our invention.

In the drawings- Figure l is a vertical section through the dimmer and a portion of a headlight to which it is attached, the section being taken on line 11 of Fig. 2; and

Figure 2 is a vertical section through the dimmer, the left side of the figure illustrating the device as broken away along line 2-2 of Fig. 1 and the right side of the figure being a section through the casing in front of the dimmer frame.

In the drawings, the headlight to which a dimmer embodying our invention is attached is designated by the numeral 1, and the'headlight includes a reflector -2, and an outer flange 3 having spaced openings 4 for detachably securing a, glass holding frame to the casing. The dimmer casing 5 which sup- 1922. Serial No. 557,903.

ports the dimming slats is provided at its inner end with projections 6 which may be engaged in the openings 4 to secure the dimmer casing to the headlight. It is obvious however that connecting means other than openings 4 and projections 6 may be employed, the only consideration being that the dimmer casing 5 be provided with connecting means for cooperation with the connecting devices on the particular headlight to which the dimmer is to be applied. The front of the dimmer casing 5 is provided with openings 7 similar to those in the headlight 1 so that the glass retaining flange 8 which is provided with projections 9 may be attached to the casing 5. The glass 10 is held in place between the flange 8 and a plurality of springs 11 which are attached to the casing 5 by clips 12 and which carry resilient buffers 13 at their glass engaging ends.

The frame for supporting the tilting slats 14 comprises a pair of spaced and parallel frame members 15 which carry a plurality of sets of aligned ears 16 and links 17 which extend between and are pivotally connected to the ears 16 of the respective sets. The pivot points 18 of each link 17 lie on a line parallel to the plurality of slats l4 and the frame thus provides a parallel motion device for supporting the several slats. To avoid the incessant noise which results when metal slats are directly mounted on a metal frame, non-metallic facing strips 19 are applied to the frame members 15. The opposite edges of the slats 14 pass through parallel slots 20 in the non-metallic arcuate strips 21 and contact with the respective facing strips 19. The strips 21 are of substantial thickness, say one-quarter inch and the walls of the slots 20 are not parallel, the upper walls on the inner strips 21 and the lower walls on the outer strips being horizontal and the opposite walls being arranged at an angle to permit the tilting movement of the slats. The strips 19 and 2l may be formed of leather or other non-metallic material and are attached to the frame members 15 in any suitable manner as by rivets 22.

As here shown, the two links 17 are diametrically opposed and lie in the vertical plane through the center of the headlight and dimmer and this is the preferred arrangement since it permits of a simple connection of the dimmer frame, to the casing 5 and. to the operating mechanism. The

casing 5 is provided with lugs 23 adjacent the links 17, and the links 17 are pivotally connected, preferably at their central points, to the respective lugs. The lugs 23 may be attached to the casing 5 in any desired manner but we preferably mount the lugs on pivot bolts 24 which are carried by straps 25. This construction permits the entire dimmer frame to be taken out of the casing 5 as a unit upon removal of the bolts 24. The lower link 17 is provided with an arm 26 which extends through a slot 27 in the casing 5 and is provided with an opening 28 to which an operating rod may be connected i The lower link 17 is provided with flanges 29 which cooperate with adjustable stop members to limit the tilting movement of the link 17. The stop members may comprise bolts 30 which pass through nuts 31 which are soldered or welded to the thin metal casing 5, and the bolts 30 are provided with lock nuts 32. To normally maintain the slats 14 in horizontal or non-dimming position, the upper lug 23 carries a spring 33 which engages the outer pivot pin 18 and urges it upwardly.

To positively obstruct all light rays which are directed above the horizontal it is essential that the forward edge of any slat should be at or below the level of the rear edge of the next lower slat when the slats are tilted into dimming position. The range of vertical movement of the frame members within the casing 5 is necessarily limited but by means of the construction shown the vertical displacement of the opposite ends of the slats is equal to twice the vertical displacement of the frame members with respect to the casing. In actual use we have found that a dimmer employing a plurality of slats one and three-quarters inches wide and spaced one-quarter inch apart will effectively obstruct the glare of the headlight while affording full illumination of the road from thirty to fifty feet in front of the machine, and will cause practically no decrease in the full volume of light when the-slats are in the normal. or non-dimming position. Since the frame members move in opposite directions to tilt the slats, the vertical movement of each frame member need be but slightly in excess of one-eighth inch to secure the desired dimming.

The specific slat size and spacing above stated is given merely by way of example and it is obvious that many changes may be made in the various parts. their relative size, shape and location within the spirit of our invention as defined in the following claims:

We claim 1. In a dimming device, a set of parallel slats, a pair of frame members at the opposite sides of said set of slats and each of said frame members providing a pivotal support for each of said slats, and means for moving said frame members in opposite d1- rections to tilt said slats.

2. In a dimming device, a pair of spaced frame members, a plurality of parallel slats between and having their opposite edges pivotally supported on said frame members, and means for moving said frame members in opposite directions to tilt said slats.

3. In a dimming device a plurality of parallel slats, a frame comprising a pair of spaced frame members arranged at the opposite sides of said slats, non-metallic means between said slats and frame members and providing pivotal supports for the opposite edges of said slats, and means to move one of said frame members to tilt said slats.

4. The combination with a dimming frame comprising a pair of spaced frame members, a plurality of parallel slats located between and having their opposite edges pivotally supported on said frame members, a plurality of links pivotally connecting said frame members, each of said links having the pivot points thereof located on a line parallel to said slats, of means including pivotal supports for said links for attaching said dimming frame to a headlight and means for spifting said frame members to tilt said s ats.

5. The combination with a dimming frame comprising a pair of spaced frame members, a plurality of parallel slats located between said frame members, non-metallic means on said frame members for pivotally supporting the opposite edges of said slats. a plurality of links pivotally connecting said frame members, each of said links .havmg the pivot points thereof located on a line parallel to said slats, of means including pivotal supports for said links for attaching said dimming frame to a headlight and means for shifting said frame members to tilt said slats.

6. In a. dimming device, a pair of spaced frame members having facings of nonmetallic material on their adjacent sides, non-metallic strips on said facing members and having a plurality of parallel slots. a plurality of parallel metal slats having their opposite edges arranged within the slots of said slotted strips, a plurality of links pivotally connecting said frame members, each of said links having the pivot points thereof located on a line parallel to said slats, means for pivotally supporting said links from a headlight and means for shifting said frame members to tilt said slats.

7. In a dimming device, a dimmer casing having means for connecting the same to the front of a headlight, a pair of spaced frame members, a plurality of horizontal slats between and having their opposite edges pivotally supported by said frame members, links pivotally connecting said frame members, each of said links having the pivot points thereof located on a line parallel to said slats, means carried by said casing providing pivot supports for said links and means for shifting said frame members to tilt said slats.

8. In a dimming device, a dimmer casing having means for connecting the same to the front of a headlight, a pair of spaced frame members, a plurality of horizontal slats between and having their opposite edges pivotally supported by said frame members, links pivotally connecting said frame members, each of said links having the pivot points thereof located on a line parallel to said slats, lugs carried by said casing adjacent said links, means pivotally connecting an intermediate portion of each of said links to the lug adjacent thereto, means for tilting one of said links ,to shift said frame members and thereby tilt said slats and means carried by said casing and cooperating with one of said links to limit the movement of said frame members and slats.

9. In a dimming device, a dimmer casing having means for connecting the same to the front of a headli ht, a plurality of parallel slats located wit in said casing, a frame mounted in said casing and providing a parallel motion support for said slats, means for operating said frame to tilt said slats, and adjustable stop means for limiting the tilting movement of said slats.

10. In a dimming device, a dimmer casing having means for connecting the same to the front of a headlight, a plurality of parallel slats located within said casing, a frame mounted in said casing and comprising a pair of spaced frame members and links pivotally connecting the same, means for tilting one of said links to shift said frame members and thereby tilt said slats, and stop mechanism on said casing and co operating with said' frame to limit the movementof said frame members and slats.

In testimony whereof, we afiix our signa-- tures.

PAUL BIEBBRAUER. IRVIN DUNCAN PETERS. 

